A 'Shadow player' is a term refered to define a player/person wich is apart from the community but he was doing the same things that the others pro players by itself, alone.
Soon or later, shadow players comes to light to introduce themselves, may by the forums, may by their own times made public.
In CTR history, there wasn't many shadow players. A good example is ntropy44, fernandomingroni/qwerty (though is was a faker, he knew the enough pro techniques to be cosidered a top player)
In the early CTR World, it can be named as shadow players the spaniards guys SkanDu and ErManu since they were as good as Thomas60, Kang or stelzig when they introduce themselves to the little yet CTR community.
It can't be named shadow players to all the players who suddenly enters the CTR world with an intermediate level. A shadow player is considered a new player who suddenly enters into the CTR world with average pro times.
By this, nowadays it can be considered a shadow player the one who enters into the ranking or the CTR world as an average Titan B to up.